Bifurcated endovascular prosthesis having tethered contralateral leg

ABSTRACT

An endovascular delivery system includes a bifurcated and inflatable prosthesis including a main tubular body having an open end and opposed ipsilateral and contralateral legs defining a graft wall therein between. A tether is disposed securably disposed to the contralateral leg, and the contralateral leg is releasably restrained towards the ipsilateral leg tether to prevent undesirable movement of the contralateral leg. A release wire within the endovascular delivery system releasably retains the tether near the ipsilateral leg.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/823,076, filed Aug. 11,2015, which is a continuation of U.S.application Ser. No. 13/803,067, filed Mar. 14, 2013, now U.S. Pat. No.9,132,025, granted Sep. 15, 2015, which claims the benefit of U.S.Provisional Application No. 61/660,105, filed Jun. 15, 2012, thecontents of all of which are incorporated by reference herein.

FIELD OF THE INVENTION

The present invention is related to an endovascular delivery system foran endovascular prosthesis. More particularly, the present invention isrelated to an endovascular delivery system having a bifurcated andinflatable prosthesis having a tether from a contralateral leg torestrain movement of the contralateral leg with respect to anipsilateral leg of the prosthesis.

BACKGROUND OF THE INVENTION

An aneurysm is a medical condition indicated generally by an expansionand weakening of the wall of an artery of a patient. Aneurysms candevelop at various sites within a patient's body. Thoracic aorticaneurysms (TAAs) or abdominal aortic aneurysms (AAAs) are manifested byan expansion and weakening of the aorta which is a serious and lifethreatening condition for which intervention is generally indicated.Existing methods of treating aneurysms include invasive surgicalprocedures with graft replacement of the affected vessel or body lumenor reinforcement of the vessel with a graft.

Surgical procedures to treat aortic aneurysms can have relatively highmorbidity and mortality rates due to the risk factors inherent tosurgical repair of this disease as well as long hospital stays andpainful recoveries. This is especially true for surgical repair of TAAs,which is generally regarded as involving higher risk and more difficultywhen compared to surgical repair of AAAs. An example of a surgicalprocedure involving repair of a AAA is described in a book titledSurgical Treatment of Aortic Aneurysms by Denton A. Cooley, M.D.,published in 1986 by W.B. Saunders Company.

Due to the inherent risks and complexities of surgical repair of aorticaneurysms, endovascular repair has become a widely-used alternativetherapy, most notably in treating AAAs. Early work in this field isexemplified by Lawrence, Jr. et al. in “Percutaneous Endovascular GraftExperimental Evaluation”, Radiology (May 1987) and by Mirich et al. in“Percutaneously Placed Endovascular Grafts for Aortic Aneurysms:Feasibility Study,” Radiology (March 1989). Commercially availableendoprostheses for the endovascular treatment of AAAs include theEndurant™ and Talent™ Abdominal Stent Grafts sold by Medtronic, Inc. ofMinneapolis, Minn.; the Zenith Flex® AAA Endovascular Graft and theZenith TX2® TAA Endovascular Graft, both sold by Cook Medical, Inc. ofBloomington, Ind.; the AFX™ Endovascular AAA system sold by Endologix,Inc. of Irvine, Calif.; and the Gore® Excluder® AAA Endoprosthesis soldby W.L. Gore & Associates, Inc. of Flagstaff, Ariz. A commerciallyavailable stent graft for the treatment of TAAs is the Gore® TAG®Thoracic Endoprosthesis sold by W.L. Gore & Associates, Inc. ofFlagstaff, Ariz.

When deploying devices by catheter or other suitable instrument, it isadvantageous to have a flexible and low profile stent graft and deliverysystem for passage through the various guiding catheters as well as thepatient's sometimes tortuous anatomy. Many of the existing endovasculardevices and methods for treatment of aneurysms, while representingsignificant advancement over previous devices and methods, use systemshaving relatively large transverse profiles, often up to 24 French.Also, such existing systems have greater than desired lateral stiffness,which can complicate the delivery process. In addition, the sizing ofstent grafts may be important to achieve a favorable clinical result. Inorder to properly size a stent graft, the treating facility typicallymust maintain a large and expensive inventory of stent grafts in orderto accommodate the varied sizes of patient vessels due to varied patientsizes and vessel morphologies. Alternatively, intervention may bedelayed while awaiting custom size stent grafts to be manufactured andsent to the treating facility. As such, minimally invasive endovasculartreatment of aneurysms is not available for many patients that wouldbenefit from such a procedure and can be more difficult to carry out forthose patients for whom the procedure is indicated. What have beenneeded are stent graft systems, delivery systems and methods that areadaptable to a wide range of patient anatomies and that can be safelyand reliably deployed using a flexible low profile system.

SUMMARY OF THE INVENTION

In one aspect of the present invention an endovascular delivery systemincludes a bifurcated and inflatable prosthesis including a main tubularbody having an open end and opposed ipsilateral and contralateral legsdefining a graft wall therein between, the ipsilateral and contralaterallegs having open ends, and the main tubular body and the ipsilateral andcontralateral legs having inflatable channels; the ipsilateral legincluding an ipsilateral tab extending from the open end of theipsilateral leg, the tab including at least two holes; an elongateguidewire having at least two outwardly projecting members, theoutwardly projecting members being sized to at least partially fitwithin the at least one of the at least two holes of the ipsilateraltab; a release wire slidable disposed within the at least two outwardlyprojecting members of the elongate guidewire and within one of the atleast two holes of the ipsilateral tab; and a tether having opposedcontralateral and ipsilateral ends, the contralateral end of the tetherbeing securably disposed at the open end of the contralateral leg, theipsilateral end of the tether having a hole, the release wire beingslidably disposed through the hole of the tether to so engage thetether; wherein withdrawal of the release wire releases the ipsilateraltab and the tether from the elongate guidewire. The elongate guidewiremay be extendable through the ipsilateral leg and through the maintubular body.

When the release wire engages the tether, the open end of thecontralateral leg is proximally disposed and restrained towards the openend of the ipsilateral leg. In such a restrained position, thecontralateral leg is restricted from significant longitudinal movementso as to prevent bunching up of the contralateral leg and is also isrestricted from significant rotational movement so as to preventmisalignment within a bodily lumen.

The endovascular delivery system may further include an elongate outertubular sheath having an open lumen and opposed proximal and distal endswith a medial portion therein between, the proximal end of the outertubular sheath securably disposed to a first handle; an elongate innertubular member having a tubular wall with an open lumen and opposedproximal and distal ends with a medial portion therein between, theinner tubular member having a longitudinal length greater than alongitudinal length of the outer tubular sheath, the inner tubularmember being slidably disposed within the open lumen of the outertubular sheath, the proximal end of the inner tubular member securablydisposed to a second handle; the elongate guidewire slidably disposedwithin the inner tubular member; the distal end of the outer tubularsheath being slidably disposed past and beyond the distal end of theinner tubular member to define a prosthesis delivery state and slidablyretractable to the medial portion of the inner tubular member to definea prosthesis unsheathed state.

The prosthesis may include non-textile polymeric material; for example,polytetrafluoroethylene. In some embodiments, thepolytetrafluoroethylene may be non-porous polytetrafluoroethylene. Theprosthesis may further include a metallic expandable member securablydisposed at or near the open end of the main tubular body of theprosthesis.

In another aspect of the present invention, a method for delivering abifurcated prosthesis, includes providing a bifurcated and inflatableprosthesis including: a main tubular body having an open end and opposedipsilateral and contralateral legs defining a graft wall thereinbetween, the ipsilateral and contralateral legs having open ends, andthe main tubular body and the ipsilateral and contralateral legs havinginflatable channels; the ipsilateral leg including an ipsilateral tabextending from the open end of the ipsilateral leg, the tab including atleast two holes; providing an elongate guidewire having at least twooutwardly projecting members, the outwardly projecting members beingsized to at least partially fit within at least one of the at least twoholes of the ipsilateral tab; providing a release wire slidable disposedwithin the at least two outwardly projecting members of the elongateguidewire and within the at least two holes of the ipsilateral tab;providing a tether having opposed contralateral and ipsilateral ends,the contralateral end of the tether being securably disposed at the openend of the contralateral leg, the ipsilateral end of the tether having ahole, the release wire being slidably disposed through the hole of thetether to so engage the tether; and withdrawing the release wire torelease the ipsilateral tab and the tether from the elongate guidewire.

When the release wire engages the tether, the open end of thecontralateral leg is proximally disposed and restrained towards the openend of the ipsilateral leg and the contralateral leg is restricted fromsignificant longitudinal movement so as to prevent bunching up of thecontralateral leg. The contralateral leg is also restricted fromsignificant rotational movement so as to prevent misalignment within abodily lumen.

In some aspects of the present invention, the endovascular prosthesismay be a modular endovascular graft assembly including a bifurcated maingraft member formed from a supple graft material having a main fluidflow lumen therein. The main graft member may also include anipsilateral leg with an ipsilateral fluid flow lumen in communicationwith the main fluid flow lumen, a contralateral leg with a contralateralfluid flow lumen in communication with the main fluid flow lumen and anetwork of inflatable channels disposed on the main graft member. Thenetwork of inflatable channels may be disposed anywhere on the maingraft member including the ipsilateral and contralateral legs. Thenetwork of inflatable channels may be configured to accept a hardenablefill or inflation material to provide structural rigidity to the maingraft member when the network of inflatable channels is in an inflatedstate. The network of inflatable channels may also include at least oneinflatable cuff disposed on a proximal portion of the main graft memberwhich is configured to seal against an inside surface of a patient'svessel. The fill material can also have transient or chronic radiopacityto facilitate the placement of the modular limbs into the main graftmember. A proximal anchor member may be disposed at a proximal end ofthe main graft member and be secured to the main graft member. Theproximal anchor member may have a self-expanding proximal stent portionsecured to a self-expanding distal stent portion with struts having across sectional area that is substantially the same as or greater than across sectional area of proximal stent portions or distal stent portionsadjacent the strut. At least one ipsilateral graft extension having afluid flow lumen disposed therein may be deployed with the fluid flowlumen of the graft extension sealed to and in fluid communication withthe fluid flow lumen of the ipsilateral leg of the main graft member. Atleast one contralateral graft extension having a fluid flow lumendisposed therein may be deployed with the fluid flow lumen of the graftextension sealed to and in fluid communication with the fluid flow lumenof the contralateral leg of the main graft member. For some embodiments,an outside surface of the graft extension may be sealed to an insidesurface of the contralateral leg of the main graft when the graftextension is in a deployed state. For some embodiments, the axial lengthof the ipsilateral and contralateral legs may be sufficient to provideadequate surface area contact with outer surfaces of graft extensions toprovide sufficient friction to hold the graft extensions in place. Forsome embodiments, the ipsilateral and contralateral legs may have anaxial length of at least about 2 cm. For some embodiments, theipsilateral and contralateral legs may have an axial length of about 2cm to about 6 cm; more specifically, about 3 cm to about 5 cm.

In another aspect of the present invention, an endovascular prosthesismay include a bifurcated and inflatable prosthesis having a main tubularbody having an open end and opposed ipsilateral and contralateral legsdefining a graft wall therein between, where the ipsilateral andcontralateral legs have open ends, and further where the main tubularbody and the ipsilateral and contralateral legs have inflatablechannels; and a web of biocompatible material disposed between thecontralateral leg and the ipsilateral leg and secured to thecontralateral leg and the ipsilateral leg. The inclusion of the web withthe endovascular prosthesis may prevent, restrict or inhibit thecontralateral leg from significant longitudinal movement so as toprevent bunching up of the contralateral leg during delivery of theendovascular prosthesis. The inclusion of the web with the endovascularprosthesis may also prevent, restrict or inhibit significant rotationalmovement of the contralateral leg during delivery so as to preventmisalignment within a bodily lumen. The web may be releasably secured tothe contralateral leg and the ipsilateral leg.

These and other features and advantages of the present invention willbecome apparent from the following detailed description of illustrativeembodiments thereof, which is to be read in connection with theaccompanying drawings. Corresponding reference element numbers orcharacters indicate corresponding parts throughout the several views ofthe drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an initial deployment state of the endovascular deliverysystem of the present invention within a patient's vasculature.

FIG. 2 depicts a deployment state of the endovascular delivery system ofthe present invention within a patient's vasculature after withdrawal ofan outer sheath.

FIG. 3 depicts a deployment state of the endovascular delivery system ofthe present invention within a patient's vasculature after an initialand partial stent deployment.

FIG. 4 depicts a deployment state of the endovascular delivery system ofthe present invention within a patient's vasculature after a stentdeployment.

FIG. 5 depicts a deployed bifurcated endovascular prosthesis with graftleg extensions.

FIG. 6 is a side elevational view of the endovascular delivery system ofthe present invention.

FIG. 7 is a side elevational and partial cutaway view of the distalportion of the endovascular delivery system of the present invention.

FIG. 8 is a partial perspective and partial cutaway view of the distalportion of the endovascular delivery system of the present invention.

FIG. 9 is an elevational view of the prosthesis of the present inventionhaving a flap at the ipsilateral leg.

FIG. 10 is a partial elevational view of a distal stop on a deliveryguidewire for restraining the ipsilateral leg of the prosthesis duringcertain delivery stages of the prosthesis.

FIG. 11 is an exploded and partial cut-away view of the distal stopinitially engaging the ipsilateral leg flap.

FIG. 12 is an exploded and partial cut-away view of the distal stopengaging the ipsilateral leg flap.

FIG. 13 is a schematic depiction of the ends of the contralateral andipsilateral graft legs having a contralateral tether.

FIG. 14 is a schematic depiction of a release wire releasably engaging aportion of the tether of FIG. 13.

FIGS. 15 through 18 depict alternate embodiments of the presentinvention for restraining the contralateral leg.

FIGS. 19 through 21 depict further alternate embodiments of the presentinvention for restraining the contralateral leg.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the invention are directed generally to methods anddevices for treatment of fluid flow vessels with the body of a patient.Treatment of blood vessels is specifically indicated for someembodiments, and, more specifically, treatment of aneurysms, such asabdominal aortic aneurysms. With regard to graft embodiments discussedherein and components thereof, the term “proximal” refers to a locationtowards a patient's heart and the term “distal” refers to a locationaway from the patient's heart. With regard to delivery system cathetersand components thereof discussed herein, the term “distal” refers to alocation that is disposed away from an operator who is using thecatheter and the term “proximal” refers to a location towards theoperator.

FIG. 1 illustrates an embodiment of a deployment sequence of anembodiment of an endovascular prosthesis (not shown), such as a modularstent graft assembly. For endovascular methods, access to a patient'svasculature may be achieved by performing an arteriotomy or cut down tothe patient's femoral artery or by other common techniques, such as thepercutaneous Seldinger technique. For such techniques, a delivery sheath(not shown) may be placed in communication with the interior of thepatient's vessel such as the femoral artery with the use of a dilatorand guidewire assembly. Once the delivery sheath is positioned, accessto the patient's vasculature may be achieved through the delivery sheathwhich may optionally be sealed by a hemostasis valve or other suitablemechanism. For some procedures, it may be necessary to obtain access viaa delivery sheath or other suitable means to both femoral arteries of apatient with the delivery sheaths directed upstream towards thepatient's aorta. In some applications a delivery sheath may not beneeded and the delivery catheter of the present invention may bedirectly inserted into the patient's access vessel by either arteriotomyor percutaneous puncture. Once the delivery sheath or sheaths have beenproperly positioned, an endovascular delivery catheter or system,typically containing an endovascular prosthesis such as but not limitedto an inflatable stent-graft, may then be advanced over a guidewirethrough the delivery sheath and into the patient's vasculature.

FIG. 1 depicts the initial placement of the endovascular delivery system100 of the present invention within a patient's vasculature. Theendovascular delivery system 100 may be advanced along a guidewire 102proximally upstream of blood flow into the vasculature of the patientincluding iliac arteries 14, 16 and aorta 10 shown in FIG. 1. While theiliac arties 14, 16 may be medically described as the right and leftcommon iliac arteries, respectively, as used herein iliac artery 14 isdescribed as an ipsilateral iliac artery and iliac artery 16 isdescribed as a contralateral iliac artery. The flow of the patient'sblood (not shown) is in a general downward direction in FIG. 1. Othervessels of the patient's vasculature shown in FIG. 1 include the renalarteries 12 and hypogastric arteries 18.

The endovascular delivery system 100 may be advanced into the aorta 10of the patient until the endovascular prosthesis (not shown) is disposedsubstantially adjacent an aortic aneurysm 20 or other vascular defect tobe treated. The portion of the endovascular delivery system 100 that isadvance through bodily lumens is in some embodiments a low profiledelivery system; for example, having an overall outer diameter of lessthan 14 French. Other diameters are also useful, such as but not limitedto less than 12 French, less than 10 French, or any sizes from 10 to 14French or greater. Once the endovascular delivery system 100 is sopositioned, an outer sheath 104 of the endovascular delivery system 100may be retracted distally so as to expose the prosthesis (not shown)which has been compressed and compacted to fit within the inner lumen ofthe outer sheath 104 of the endovascular delivery system 100.

As depicted in FIG. 2, once the endovascular delivery system 100 is sopositioned, the outer sheath 104 of the endovascular delivery system 100may be retracted distally so as to expose the endovascular prosthesis106 which has been compressed and compacted to fit within the innerlumen of the outer sheath 104 of the endovascular delivery system 100.The outer sheath 104 may be formed of a body compatible material. Insome embodiments, the biocompatible material may be a biocompatiblepolymer. Examples of suitable biocompatible polymers may include, butare not limited to, polyolefins such as polyethylene (PE), high densitypolyethylene (HDPE) and polypropylene (PP), polyolefin copolymers andterpolymers, polytetrafluoroethylene (PTFE), polyethylene terephthalate(PET), polyesters, polyamides, polyurethanes, polyurethaneureas,polypropylene and, polycarbonates, polyvinyl acetate, thermoplasticelastomers including polyether-polyester block copolymers andpolyamide/polyether/polyesters elastomers, polyvinyl chloride,polystyrene, polyacrylate, polymethacrylate, polyacrylonitrile,polyacrylamide, silicone resins, combinations and copolymers thereof,and the like. In some embodiments, the biocompatible polymers includepolypropylene (PP), polytetrafluoroethylene (PTFE), polyethyleneterephthalate (PET), high density polyethylene (HDPE), combinations andcopolymers thereof, and the like. Useful coating materials may includeany suitable biocompatible coating. Non-limiting examples of suitablecoatings include polytetrafluoroethylene, silicone, hydrophilicmaterials, hydrogels, and the like. Useful hydrophilic coating materialsmay include, but are not limited to, alkylene glycols, alkoxypolyalkylene glycols such as methoxypolyethylene oxide, polyoxyalkyleneglycols such as polyethylene oxide, polyethylene oxide/polypropyleneoxide copolymers, polyalkylene oxide-modified polydimethylsiloxanes,polyphosphazenes, poly(2-ethyl-2-oxazoline), homopolymers and copolymersof (meth) acrylic acid, poly(acrylic acid), copolymers of maleicanhydride including copolymers of methylvinyl ether and maleic acid,pyrrolidones including poly(vinylpyrrolidone) homopolymers andcopolymers of vinyl pyrrolidone, poly(vinylsulfonic acid), acryl amidesincluding poly(N-alkylacrylarnide), poly(vinyl alcohol),poly(ethyleneimine), polyamides, poly(carboxylic acids), methylcellulose, carboxymethylcellulose, hydroxypropyl cellulose,polyvinylsulfonic acid, water soluble nylons, heparin, dextran, modifieddextran, hydroxylated chitin, chondroitin sulphate, lecithin,hyaluranon, combinations and copolymers thereof, and the like.Non-limiting examples of suitable hydrogel coatings include polyethyleneoxide and its copolymers, polyvinylpyrrolidone and its derivatives;hydroxyethylacrylates or hydroxyethyl(meth)acrylates; polyacrylic acids;polyacrylamides; polyethylene maleic anhydride, combinations andcopolymers thereof, and the like. In some embodiments, the outer sheath104 may be made of polymeric materials, e.g., polyimides, polyesterelastomers (Hytrel®), or polyether block amides (Pebax®),polytetrafluoroethylene, and other thermoplastics and polymers. Theoutside diameter of the outer sheath 104 may range from about 0.1 inchto about 0.4 inch. The wall thickness of the outer sheath 104 may rangefrom about 0.002 inch to about 0.015 inch. The outer sheath 104 may alsoinclude an outer hydrophilic coating. Further, the outer sheath 104 mayinclude an internal braided or otherwise reinforced portion of eithermetallic or polymeric filaments. In addition to being radiallycompressed when disposed within an inner lumen of the outer sheath 104of the endovascular delivery system 100, a proximal stent 108 may beradially restrained by high strength flexible belts 110 in order tomaintain a small profile and avoid engagement of the proximal stent 108with a body lumen wall until deployment of the proximal stent 108 isinitiated. The belts 110 can be made from any high strength, resilientmaterial that can accommodate the tensile requirements of the beltmembers and remain flexible after being set in a constrainingconfiguration. Typically, belts 110 are made from solid ribbon or wireof a shape memory alloy such as nickel titanium or the like, althoughother metallic or polymeric materials are possible. Belts 110 may alsobe made of braided metal filaments or braided or solid filaments of highstrength synthetic fibers such as Dacron®, Spectra or the like. Anoutside transverse cross section of the belts 110 may range from about0.002 to about 0.012 inch, specifically, about 0.004 to about 0.007inch. The cross sections of belts 110 may generally take on any shape,including rectangular (in the case of a ribbon), circular, elliptical,square, etc. The ends of the belts 110 may be secured by one or morestent release wires or elongate rods 112 which extend through loopedends (not shown) of the belts 110. The stent release wires or elongaterods 112 may be disposed generally within the prosthesis 106 duringdelivery of the system 100 to the desired bodily location. For example,the stent release wires or elongate rods 112 may enter and exit theguidewire lumen 122 or other delivery system lumen as desired to affectcontrolled release of the stent 108, including if desired controlled andstaged release of the stent 108. Once the outer sheath 104 of theendovascular delivery system 100 has been retracted, the endovasculardelivery system 100 and the endovascular prosthesis 106 may be carefullypositioned in an axial direction such that the proximal stent 108 isdisposed substantially even with the renal arteries.

In some embodiments, the endovascular prosthesis 106 includes aninflatable graft 114. The inflatable graft may be a bifurcated grafthaving a main graft body 124, an ipsilateral graft leg 126 and acontralateral graft leg 128. The inflatable graft 114 may furtherinclude a fill port 116 in fluid communication with an inflation tube118 of the endovascular delivery system 100 for providing an inflationmedium (not shown). The distal portion of the endovascular deliverysystem 100 may include a nosecone 120 which provides an atraumaticdistal portion of the endovascular delivery system 100. The guidewire102 is slidably disposed within a guidewire lumen 122 of theendovascular delivery system 100.

As depicted in FIG. 3, deployment of the proximal stent 108 may beginwith deployment of the distal portion 130 of stent 108 by retracting thestent release wire or rod 112 that couples ends of belt 110 restrainingthe distal portion 130 of the stent 108. The distal portion 130 of stent108 may be disposed to the main graft body 124 via a connector ring 142.The stent 108 and/or the connector ring 142 may be made from or includeany biocompatible material, including metallic materials, such as butnot limited to, nitinol (nickel titanium), cobalt-based alloy such asElgiloy, platinum, gold, stainless steel, titanium, tantalum, niobium,and combinations thereof. The present invention, however, is not limitedto the use of such a connector ring 142 and other shaped connectors forsecuring the distal portion 130 of the stent 108 at or near the end ofthe main graft body 124 may suitably be used. Additional axialpositioning typically may be carried out even after deploying the distalportion 130 of the stent 108 as the distal portion 130 may provide onlypartial outward radial contact or frictional force on the inner lumen ofthe patient's vessel or aorta 10 until the proximal portion 132 of thestent 108 is deployed. Once the belt 110 constraining the proximalportion 132 of the stent 108 has been released, the proximal portion 132of the stent 108 self-expands in an outward radial direction until anoutside surface of the proximal portion 132 of the stent 108 makescontact with and engages an inner surface of the patient's vessel 10.

As depicted in FIG. 4, after the distal portion 130 of the stent 108 hasbeen deployed, the proximal portion 132 of the stent 108 may then bedeployed by retracting the wire 112 that couples the ends of the belt110 restraining the proximal portion 132 of the stent 108. As theproximal portion 132 of the stent 108 self-expands in an outward radialdirection, an outside surface of the proximal portion 132 of the stent108 eventually makes contact with the inside surface of the patient'saorta 10. For embodiments that include tissue engaging barbs (not shown)on the proximal portion 132 of the stent 108, the barbs may also beoriented and pushed in a general outward direction so as to make contactand engage the inner surface tissue of the patient's vessel 10, whichfurther secures the proximal stent 108 to the patient's vessel 10.

Once the proximal stent 108 has been partially or fully deployed, theproximal inflatable cuff 134 may then be filled through the inflationport 116 with inflation material injected through an inflation tube 118of the endovascular delivery system 100 which may serve to seal anoutside surface of the inflatable cuff 134 to the inside surface of thevessel 10. The remaining network of inflatable channels 136 may also befilled with pressurized inflation material at the same time whichprovides a more rigid frame like structure to the inflatable graft 114.For some embodiments, the inflation material may be a biocompatible,curable or hardenable material that may cured or hardened once thenetwork of inflatable channels 136 are filled to a desired level ofmaterial or pressure within the network or after passage of apredetermined period of time. Some embodiments may also employradiopaque inflation material to facilitate monitoring of the fillprocess and subsequent engagement of graft extensions (not shown). Thematerial may be cured by any of the suitable methods discussed hereinincluding time lapse, heat application, application of electromagneticenergy, ultrasonic energy application, chemical adding or mixing or thelike. Some embodiments for the inflation material that may be used toprovide outward pressure or a rigid structure from within the inflatablecuff 134 or network of inflatable channels 136 may include inflationmaterials formed from glycidyl ether and amine materials. Some inflationmaterial embodiments may include an in situ formed hydrogel polymerhaving a first amount of diamine and a second amount of polyglycidylether wherein each of the amounts are present in a mammal or in amedical device, such as an inflatable graft, located in a mammal in anamount to produce an in situ formed hydrogel polymer that isbiocompatible and has a cure time after mixing of about 10 seconds toabout 30 minutes and wherein the volume of said hydrogel polymer swellsless than 30 percent after curing and hydration. Some embodiments of theinflation material may include radiopaque material such as sodiumiodide, potassium iodide, barium sulfate, Visipaque 320, Hypaque,Omnipaque 350, Hexabrix and the like. For some inflation materialembodiments, the polyglycidyl ether may be selected fromtrimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether,polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether,diglycerol polyglycidyl ether, glycerol polyglycidyl ether,trimethylolpropane polyglycidyl ether, polyethylene glycol diglycidylether, resorcinol diglycidyl ether, glycidyl ester ether of p-hydroxybenzoic acid, neopentyl glycol diglycidyl ether, 1,6-hexanedioldiglycidyl ether, bisphenol A (PO)₂ diglycidyl ether, hydroquinonediglycidyl ether, bisphenol S diglycidyl ether, terephthalic aciddiglycidyl ester, and mixtures thereof. For some inflation materialembodiments, the diamine may be selected from (poly)alkylene glycolhaving amino or alkylamino termini selected from the group consisting ofpolyethylene glycol (400) diamine, di-(3-aminopropyl) diethylene glycol,polyoxypropylenediamine, polyetherdiamine, polyoxyethylenediamine,triethyleneglycol diamine and mixtures thereof. For some embodiments,the diamine may be hydrophilic and the polyglycidyl ether may behydrophilic prior to curing. For some embodiments, the diamine may behydrophilic and the polyglycidyl ether is hydrophobic prior to curing.For some embodiments, the diamine may be hydrophobic and thepolyglycidyl ether may be hydrophilic prior to curing.

The network of inflatable channels 136 may be partially or fullyinflated by injection of a suitable inflation material into the mainfill port 116 to provide rigidity to the network of inflatable channels136 and the graft 114. In addition, a seal is produced between theinflatable cuff 134 and the inside surface of the abdominal aorta 10.Although it is desirable to partially or fully inflate the network ofinflatable channels 136 of the graft 114 at this stage of the deploymentprocess, such inflation step optionally may be accomplished at a laterstage if necessary.

Once the graft 114 is deployed and the inflatable channels 136 thereofhave been filled and expanded, another delivery catheter (not shown) maybe used to deploy a contralateral graft extension 138, as depicted inFIG. 5. The contralateral graft extension 138 is in an axial positionwhich overlaps the contralateral leg 128 of the graft 114. The amount ofdesired overlap of the graft extension 138 with the contralateral leg128 may vary depending on a variety of factors including vesselmorphology, degree of vascular disease, patient status and the like.However, for some embodiments, the amount of axial overlap between thecontralateral graft extension 138 and the contralateral leg 128 may beabout 1 cm to about 5 cm; more specifically, about 2 cm to about 4 cm.Once the contralateral graft extension 138 has been deployed, anipsilateral graft extension 140 may be similarly deployed in theipsilateral graft leg 126.

For some deployment embodiments, the patient's hypogastric arteries maybe used to serve as a positioning reference point to ensure that thehypogastric arteries are not blocked by the deployment. Upon such adeployment, the distal end of a graft extension 138 or 140 may bedeployed anywhere within a length of the ipsilateral leg 126 orcontralateral leg 128 of the graft 114. Also, although only one graftextension 140, 138 is shown deployed on the ipsilateral side andcontralateral side of the graft assembly 114, additional graftextensions 140, 138 may be deployed within the already deployed graftextensions 140, 138 in order to achieve a desired length extension ofthe ipsilateral leg 126 or contralateral leg 128. For some embodiments,about 1 to about 5 graft extensions 138, 140 may be deployed on eitherthe ipsilateral or contralateral sides of the graft assembly 114.Successive graft extensions 138, 140 may be deployed within each otherso as to longitudinally overlap fluid flow lumens of successive graftextensions.

Graft extensions 138, 140, which may be interchangeable for someembodiments, or any other suitable extension devices or portions of themain graft section 124 may include a variety of suitable configurations.For some embodiments, graft extensions 138, 140 may include apolytetrafluoroethylene (PTFE) graft 142 with helical nitinol stent 144.

Further details of the endovascular prosthesis 106 and/or graftextensions 138, 140 may be found in commonly owned U.S. Pat. Nos.6,395,019; 7,081,129; 7,147,660; 7,147,661; 7,150,758; 7,615,071;7,766,954 and 8,167,927 and commonly owned U.S. Published ApplicationNo. 2009/0099649, the contents of all of which are incorporated hereinby reference in their entirety. Details for the manufacture of theendovascular prosthesis 106 may be found in commonly owned U.S. Pat.Nos. 6,776,604; 7,090,693; 7,125,464; 7,147,455; 7,678,217 and7,682,475, the contents of all of which are incorporated herein byreference in their entirety. Useful inflation materials for theinflatable graft 114 may be found in may be found in commonly owned U.S.Published Application No. 2005/0158272 and 2006/0222596, the contents ofall of which are incorporated herein by reference in their entirety.Additional details of an endovascular delivery system having an improvedradiopaque marker system for accurate prosthesis delivery may be foundin commonly owned U.S. Provisional Application No. 61/660,413, entitled“Endovascular Delivery System With An Improved Radiopaque MarkerScheme”, filed Jun. 15, 2012, and having Attorney Docket No. 1880-42P,the contents of which are incorporated the herein by reference in theirentirety.

Useful graft materials for the endovascular prosthesis 106 include, butare not limited, polyethylene; polypropylene; polyvinyl chloride;polytetrafluoroethylene (PTFE); fluorinated ethylene propylene;fluorinated ethylene propylene; polyvinyl acetate; polystyrene;poly(ethylene terephthalate); naphthalene dicarboxylate derivatives,such as polyethylene naphthalate, polybutylene naphthalate,polytrimethylene naphthalate and trimethylenediol naphthalate;polyurethane, polyurea; silicone rubbers; polyamides; polyimides;polycarbonates; polyaldehydes; polyether ether ketone; natural rubbers;polyester copolymers; silicone; styrene-butadiene copolymers;polyethers; such as fully or partially halogenated polyethers; andcopolymers and combinations thereof. In some embodiments, the graftmaterials are non-textile graft materials, e.g., materials that are notwoven, knitted, filament-spun, etc. that may be used with textilegrafts. Such useful graft material may be extruded materials.Particularly useful materials include porous polytetrafluoroethylenewithout discernable node and fibril microstructure and (wet) stretchedPTFE layer having low or substantially no fluid permeability thatincludes a closed cell microstructure having high density regions whosegrain boundaries are directly interconnected to grain boundaries ofadjacent high density regions and having substantially no node andfibril microstructure , and porous PTFE having no or substantially nofluid permeability. Such PTFE layers may lack distinct, parallel fibrilsthat interconnect adjacent nodes of ePTFE, typically have no discernablenode and fibril microstructure when viewed at a magnification of up to20,000. A porous PTFE layer having no or substantially no fluidpermeability may have a Gurley Number of greater than about 12 hours, orup to a Gurley Number that is essentially infinite, or too high tomeasure, indicating no measurable fluid permeability. Some PTFE layershaving substantially no fluid permeability may have a Gurley Number at100 cc of air of greater than about 10⁶ seconds. The Gurley Number isdetermined by measuring the time necessary for a given volume of air,typically, 25 cc, 100 cc or 300 cc, to flow through a standard 1 squareinch of material or film under a standard pressure, such as 12.4 cmcolumn of water. Such testing maybe carried out with a GurleyDensometer, made by Gurley Precision Instruments, Troy, N.Y. Details ofsuch useful PTFE materials and methods for manufacture of the same maybe found in commonly owned U.S. Patent Application Publication No.2006/0233991, the contents of which are incorporated herein by referencein their entirety.

FIG. 6 is a side elevational view of the endovascular delivery system100 of the present invention. The endovascular delivery system 100 mayinclude, among other things, the nosecone 120; the outer sheath 104; aretraction knob or handle 152 for the outer sheath 104; a flush port 154for the outer sheath 104; an outer sheath radiopaque marker band 156; aninner tubular member or hypotube 150; an inflation material or polymerfill connector port 158; an inflation material or polymer fill cap 160;a guidewire flush port 162; a guidewire flush port cap 164; a guidewireport 166; and nested stent release knobs 168; interrelated as shown. Theinner tubular member 150 may be formed from any of the above-describedmaterials for the outer sheath 104. In addition, a portion of the innertubular member 150 or even the entire inner tubular member 150 may be inthe form of a metallic hypotube. Details of useful metallic hypotubesand endovascular delivery systems containing the same may be found incommonly owned U.S. Provisional Application No. 61/660,103, entitled“Endovascular Delivery System With Flexible And Torqueable Hypotube”,Attorney Docket 1880-43P, filed Jun. 15, 2012, the contents of which areincorporated herein by reference in their entirety.

The flush port 154 for the outer sheath 104 may be used to flush theouter sheath 104 during delivery stages. The outer sheath 104 may have aradiopaque marker band to aid the practitioner in properly navigatingthe delivery system 100 to the desired bodily site. The outer sheath 104is retractable by movement of the retraction knob or handle 152 for theouter sheath 104 by a practitioner towards the proximal handle assembly170 of the delivery system 100. The inner tubular member or hypotube 150is disposed from the inner tubular member or hypotube 150 toward aproximal portion of the delivery system 100. The inflation material orpolymer fill connector port 158 and the inflation material or polymerfill cap 160 are useful for providing inflation material (e.g.,polymeric fill material) to inflate proximal inflatable cuffs 134 andthe network of inflatable channels 136 of the inflatable graft 114. Theguidewire flush port 162 and the guidewire flush port cap 164 are usefulfor flushing the guidewire port 166 during delivery stages of thedelivery system 100. The nested stent release knobs 168 contains aseries of nested knobs (not shown) that that are used to engage releasemechanisms for delivery of the endovascular prosthesis 106. Furtherdetails, including but not limited to methods, catheters and systems,for deployment of endovascular prostheses are disclosed in commonlyowned U.S. Pat. Nos. 6,761,733 and 6,733,521 and commonly owned U.S.Patent Application Publication Nos. 2006/0009833 and 2009/0099649, allof which are incorporated by reference herein in their entirety.

FIG. 7 is a side elevational and partial cutaway view of the distalportion 172 of the endovascular delivery system 100 of the presentinvention, and FIG. 8 is a partial perspective and partial cutaway viewof the distal portion 172 of the endovascular delivery system 100 of thepresent invention. The distal portion 172 of the endovascular deliverysystem 100 includes a prosthesis/stent holder 174 disposed upon aprosthesis/stent holder guidewire 176. The holder 174 is usefulreleasably securing the endovascular prosthesis 106 (not shown) withinthe delivery system 100. The holder 174 inhibits or substantiallyinhibits undesirable longitudinal and/or circumferential movement of theendovascular prostheses 106 during delivery stages of the deliverysystem 100. Belts 110 serve to restrain the endovascular prosthesis 106in a radially constrained stage until desired release of theendovascular prosthesis 106.

FIG. 9 is an elevational view of the prosthesis 106 of the presentinvention having a flap 180 at the ipsilateral leg 126. The flap 180 maybe made from any of the above-described graft materials. In someembodiments, the flap 180 is made from polytetrafluoroethylene. The flap180 may include two holes 182. The width of the flap may be from about10% to about 90% of the circumference of the ipsilateral leg 126. Insome embodiments, the width is from about 30% to about 60%; in otherembodiments, from about 45% to about 55%. The flap 182 may contain twoholes 182 as shown in FIG. 9, one hole, or more than two holes. A holediameter of about 0.06 inches is useful, although hole diameters may behigher or lower. In the case of more than one hole, the hole diametersmay vary between or among holes.

FIG. 10 is a partial elevational view of one embodiment including adistal stop 186 on a delivery guidewire 184 for restraining theipsilateral leg 126 of the prosthesis 106 during certain delivery stagesof the prosthesis 106. The distal stop 186 includes two raisedprojections 188 securably attached to a guidewire 184. A release wire190 is slidably disposed within the projections 188. As depicted inFIGS. 11 and 12, the distal stop 186 is useful for releasably securingthe ipsilateral leg 126, in particular the flap 180, to the distal stop186 and the guidewire 184. The raised projections 188 may be secured ordisposed within one or both of the flap holes 182. The release wire 190is thus releasably inter-looped or inter-laced within or to the flap180.

FIG. 13 is a schematic depiction of the ends of the contralateral andipsilateral graft legs 128, 126 of the prosthesis 106 having acontralateral tether 192. The contralateral tether 192 has acontralateral end 196 and an opposed ipsilateral end 198. Thecontralateral end 196 is securably disposed to the end of thecontralateral leg 128. The contralateral tether 192 may also be madefrom any of the above-described graft materials. In some embodiments,the contralateral tether 192 is made from polytetrafluoroethylene. Asdepicted in FIGS. 13 and 14, the release wire 190 releasably engages aportion of the tether 192. In some embodiments, the release wire 190 isslidably disposed through a hole 194 near the ipsilateral end 198 of thetether 192 as depicted in FIG. 13. When the release wire 190 is engagedwith the tether 192, undesirably longitudinal movement, such asbunching, of the contralateral leg 128 is mitigated or even prevented asthe contralateral leg 128 is ultimately and relatively restrained by therelease wire and the ipsilateral leg 126 is relatively restrained by thedistal stop 186 and the release wire 190. The contralateral tether 192may also mitigate or prevent undesirable rotation of the contralateralleg 128 with respect to the ipsilateral leg 126 when the tether 192 isso engaged with the release wire 190.

In some embodiments, the tether 192 can withstand aggressive cannulationwithout disconnecting from the contralateral leg 128. For example, thetether 192 may have a tensile strength greater than 0.5 pounds-force persquare inch (psi), which is an approximate maximum force which may beapplied clinically. The tether 192 may have a tensile strength of about2.0 psi. Such a tensile strength is non-limiting. Use of thecontralateral tether 192 also allows filling of the inflatable graft 114without impingement of the fill tube 116 or the network of channels 136.In the case of narrow distal aortic necks or in acute aortoiliac angles,a “ballerina” type crossover configuration (also referred to as a“barber pole: configuration) of the ipsilateral and contralateral graftlegs may be used by a practitioner. In such a “ballerina” type crossoverconfiguration the two iliac graft limbs may cross each other one or moretimes distal to the aortic body but before entering the iliac arteriesof a patient treated with a bifurcated graft. Such a “ballerina” typecrossover configuration may be achieved even with the use of the tether192 with the inflatable graft 114 of the present invention. Moreover,use of the tether 192 prevents undesirably leg 126, 128 flipping duringpositioning of the inflatable graft 114.

The tether 192 width may be from about 2 to 5 mm, and its length may befrom about 5 to 20 mm. These dimensions are non-limiting dimensions, andother suitable dimensions may be used. For example, in some embodiments(not shown), the contralateral tether 192 may have an ipsilateral end198 that is not configured for engagement with a release wire 190 butrather is configured to run through the inner tubular member 150 andterminate at the proximal handle assembly 170 of the delivery system andreleasably secured to a component thereof, such as an additional knob onhandle assembly 170. A longer contralateral tether 192 of such aconfiguration may be manipulated by the physician-user in the samemanner to mitigate or prevent undesirable movement or rotation of one orboth legs 126, 128 during positioning of the inflatable graft 114 asdescribed herein. This may provide beneficial positioning control ormanipulation of the legs 126, 128, as opposed to must mitigating orpreventing undesirable movement. Such a longer tether 192 would notnecessary have to come all the way out of the handle 170, butalternatively could be engaged by a control wire or other controlmechanism terminating at or near the handle 170.

The present invention, however, is not limited to the use of the tether192 to restrain the contralateral leg 128 during deployment, and othersuitably arrangements may be used. For example, as depicted in FIGS. 15and 16, the release wire 190 may be looped through a hole 200 in thecontralateral leg 128. As depicted in FIG. 17, a loop 202 of polymericmaterial, such a polytetrafluoroethylene, may be disposed between thecontralateral leg 128 and the ipsilateral leg 126. The loop 202 may bewithdrawn via a release wire (not shown) which may have only one end(not shown) the loop secured thereto. Moreover, as depicted in FIG. 18,a relatively stiffer polymeric member 204, such as a polyamide tube ofthread, may be used to restrain movement of the contralateral leg 128relative to the ipsilateral leg 126. Such a polymeric member 204 may besecured to the release wire 190 or to another release wire within thedelivery system 100. These examples of non-tethering restrains are notlimiting and other restraining arrangements may be suitably be used.

The present invention, however, is not limited to the use of theabove-described tether 192, the above-described release wire 190 and/orthe above-described a loop 202 to restrain the contralateral leg 128during deployment, and other suitably arrangements may be used. Forexample, as depicted in FIGS. 19 through 21, a web 210 may be disposedbetween the contralateral leg 128 and the ipsilateral leg 126. The web210 may be fabricated from any useful biocompatible materials, includingbiocompatible materials used to form endovascular prosthesis 106 orsections of the endovascular prosthesis 106, such as the contralateralleg 128 and/or the ipsilateral leg 126.

As depicted in FIG. 19, the web 210 may be substantially disposedbetween the contralateral leg 128 and the ipsilateral leg 126 to soconstrain relative movement of the legs 128, 126 during initial stagesof deployment of the endovascular prosthesis 106. The web 210 may be cutor otherwise separated into portions during delivery by the practitionerso as to facilitate proper placement of the contralateral leg 128 andthe ipsilateral leg 126. During delivery of the endovascular prosthesis106. Such portions may be removed by the practitioner or may remainwithin the aortic aneurysm 20. Furthermore, the web 210 may contain aweakened portion or tear-line 212. The tear-line 212 may be configuredto allow separation of one portion of the web 210 from another portionof the web 210 upon application of a displacement force (not shown) bythe practitioner to separate of properly position the contralateral leg128 and the ipsilateral leg 126 within the aortic aneurysm 20 orproximal to the aortic aneurysm 20, for example near or within the iliacarteries 14, 16. As such, the web 210 may be secured to thecontralateral leg 128 and the ipsilateral leg 126, including releasablysecured to the contralateral leg 128 and the ipsilateral leg 126.

FIG. 20 is a cross-section view of the contralateral leg 128, theipsilateral leg 126 and the web 210 taken along the 20-20 axis of FIG.19. As depicted in FIG. 20, the web 210 is a sheet of materialinter-connecting or inter-engaging the contralateral leg 128 and theipsilateral leg 126. While the web 210 is as a planar sheet in FIGS. 19and 20, the present invention is not so limited. The web 210 may benon-planar in shape (not shown), for example having slag or folded oversections to permit a degree of movement between the contralateral leg128 and the ipsilateral leg 126. Furthermore, the web 210 is not limitedto being a sheet of material. For example, the web 210 may itself beperforated, such as but not limited to a screen configuration, where theweb 210 may have interstitial openings (not shown) or openableinterstitial apertures (not shown) to permit greater flexibility over aplanar sheet of material. Moreover, as depicted in FIG. 21, a pluralityof webs 210 may suitable be used to inter-connecting or inter-engagingthe contralateral leg 128 and the ipsilateral leg 126.

The web 210 may be shaped, configured or constructed to allow more legindependent mobility at the distal portions of the legs 126, 128 ascompared to proximal leg portions near the bifurcation portion of thegraft or prosthesis 106. For example, the web 210 may have a curvedand/or indented distal edge(s) or portion(s) near the distal portions ofthe legs 126, 128, where such curved and/or indented distal web edge(s)or portion(s) allows or permits the legs 126, 128 more relativeindependent movement as compared to a regular-shaped ortriangular-shaped web 210 as depicted in FIG. 19. Such increased legindependent mobility at the distal portions of the legs 126, 128 mayalso be achieved by any suitable means. On additional, non-limitingexample includes varying the thickness of the web 210 to achieve suchincreased leg independent mobility at the distal portions of the legs126, 128. For example, portions of the web 210 near the distal portionsof the legs 126, 128 could have reduced thickness, i.e., thinner, ascompared to portions of the web 201 near the bifurcation of the graft orprosthesis 106. Further, the materials of construction of the web 210may vary such that web portions near the distal portions of the legs126, 128 include materials having greater modulus of flexibility and/orelasticity as compared materials portions of the web 201 near thebifurcation of the graft or prosthesis 106.

The following embodiments or aspects of the invention may be combined inany fashion and combination and be within the scope of the presentinvention, as follows:

Embodiment 1. An endovascular delivery system, comprising:

a bifurcated and inflatable prosthesis comprising:

-   -   a main tubular body having an open end and opposed ipsilateral        and contralateral legs defining a graft wall therein between,        said ipsilateral and contralateral legs having open ends, and        said main tubular body and said ipsilateral and contralateral        legs having inflatable channels;    -   said ipsilateral leg comprising an ipsilateral tab extending        from the open end of said ipsilateral leg, said tab comprising        at least two holes;

an elongate guidewire having at least two outwardly projecting members,said outwardly projecting members being sized to at least partially fitwithin the at least one of said at least two holes of said ipsilateraltab;

a release wire slidable disposed within the at least two outwardlyprojecting members of the elongate guidewire and within one of the atleast two holes of said ipsilateral tab; and

a tether having opposed contralateral and ipsilateral ends, saidcontralateral end of the tether being securably disposed at said openend of said contralateral leg, said ipsilateral end of the tether havinga hole, said release wire being slidably disposed through the hole ofthe tether to so engage the tether;

wherein withdrawal of the release wire releases the ipsilateral tab andthe tether from the elongate guidewire.

Embodiment 2. The endovascular delivery system of embodiment 1, wherein,when said release wire engages said tether, the open end of thecontralateral leg is proximally disposed and restrained towards the openend of the ipsilateral leg.Embodiment 3. The endovascular delivery system of embodiment 2, whereinthe contralateral leg is restricted from significant longitudinalmovement so as to prevent bunching up of the contralateral leg.Embodiment 4. The endovascular delivery system of embodiment 2, whereinthe contralateral leg is restricted from significant rotational movementso as to prevent misalignment within a bodily lumen.Embodiment 5. The endovascular delivery system of embodiment 1, whereinsaid elongate guidewire is extendable through the ipsilateral leg andthrough the main tubular body.Embodiment 6. The endovascular delivery system of embodiment 1, furthercomprising:

an elongate outer tubular sheath having an open lumen and opposedproximal and distal ends with a medial portion therein between, theproximal end of the outer tubular sheath securably disposed to a firsthandle;

an elongate inner tubular member having a tubular wall with an openlumen and opposed proximal and distal ends with a medial portion thereinbetween, the inner tubular member having a longitudinal length greaterthan a longitudinal length of the outer tubular sheath, the innertubular member being slidably disposed within the open lumen of theouter tubular sheath, the proximal end of the inner tubular membersecurably disposed to a second handle;

said elongate guidewire slidably disposed within the inner tubularmember;

the distal end of the outer tubular sheath being slidably disposed pastand beyond the distal end of the inner tubular member to define aprosthesis delivery state and slidably retractable to the medial portionof the inner tubular member to define a prosthesis unsheathed state.

Embodiment 7. The endovascular delivery system of embodiment 1, whereinthe prosthesis comprises non-textile polymeric material.Embodiment 8. The endovascular delivery system of embodiment 1, whereinthe non-textile polymeric material of the prosthesis comprises extrudedpolytetrafluoroethylene.Embodiment 9. The endovascular delivery system of embodiment 8, whereinsaid extruded polytetrafluoroethylene is non-porouspolytetrafluoroethylene.Embodiment 10. The endovascular delivery system of embodiment 1, whereinthe prosthesis further comprises a metallic expandable member securablydisposed at or near the open end of the main tubular body of saidprosthesis.Embodiment 11. A method for delivering a bifurcated prosthesis,comprising:

providing a bifurcated and inflatable prosthesis comprising:

-   -   a main tubular body having an open end and opposed ipsilateral        and contralateral legs defining a graft wall therein between,        said ipsilateral and contralateral legs having open ends, and        said main tubular body and said ipsilateral and contralateral        legs having inflatable channels;    -   said ipsilateral leg comprising an ipsilateral tab extending        from the open end of said ipsilateral leg, said tab comprising        at least two holes;

providing an elongate guidewire having at least two outwardly projectingmembers, said outwardly projecting members being sized to at leastpartially fit within at least one of said at least two holes of saidipsilateral tab;

providing a release wire slidable disposed within the at least twooutwardly projecting members of the elongate guidewire and within the atleast two holes of said ipsilateral tab;

providing a tether having opposed contralateral and ipsilateral ends,said contralateral end of the tether being securably disposed at saidopen end of said contralateral leg, said ipsilateral end of the tetherhaving a hole, said release wire being slidably disposed through thehole of the tether to so engage the tether; and

withdrawing the release wire to release the ipsilateral tab and thetether from the elongate guidewire.

Embodiment 12. The method of embodiment 11, wherein, when said releasewire engages said tether, the open end of the contralateral leg isproximally disposed and restrained towards the open end of theipsilateral leg.Embodiment 13. The method of embodiment 12, wherein the contralateralleg is restricted from significant longitudinal movement so as toprevent bunching up of the contralateral leg.Embodiment 14. The method of embodiment 12, wherein the contralateralleg is restricted from significant rotational movement so as to preventmisalignment within a bodily lumen.Embodiment 15. An endovascular prosthesis, comprising:

a bifurcated and inflatable prosthesis comprising:

-   -   a main tubular body having an open end and opposed ipsilateral        and contralateral legs defining a graft wall therein between,        said ipsilateral and contralateral legs having open ends, and        said main tubular body and said ipsilateral and contralateral        legs having inflatable channels; and    -   a web of biocompatible material disposed between the        contralateral leg and the ipsilateral leg and secured to the        contralateral leg and the ipsilateral leg;

wherein the contralateral leg is restricted from significantlongitudinal movement so as to prevent bunching up of the contralateralleg during delivery of the endovascular prosthesis.

Embodiment 16. The endovascular prosthesis of embodiment 15, wherein thecontralateral leg is restricted from significant rotational movement soas to prevent misalignment within a bodily lumen.Embodiment 17. The endovascular prosthesis of embodiment 15, wherein theweb is releasably secured to the contralateral leg and the ipsilateralleg.

While various embodiments of the present invention are specificallyillustrated and/or described herein, it will be appreciated thatmodifications and variations of the present invention may be effected bythose skilled in the art without departing from the spirit and intendedscope of the invention. Further, any of the embodiments or aspects ofthe invention as described in the claims or in the specification may beused with one and another without limitation.

1.-17. (canceled)
 18. An endovascular delivery system, comprising: abifurcated prosthesis comprising: a main tubular body having an open endand opposed ipsilateral and contralateral legs defining a graft walltherein between, said ipsilateral and contralateral legs having openends; said contralateral leg comprising having a hole through the graftwall at a location near the open end of the contralateral leg; and adelivery catheter comprising an elongate release rod or wire slidabledisposed within the delivery catheter, within the hole of thecontralateral leg and within the ipsilateral leg; wherein retraction ofthe elongate release rod or wire within the delivery catheter releasesthe contralateral leg from and the ipsilateral leg.
 19. The endovasculardelivery system of claim 18, wherein the contralateral leg is restrictedfrom significant longitudinal movement so as to prevent bunching up ofthe contralateral leg.
 20. The endovascular delivery system of claim 18,wherein the contralateral leg is restricted from significant rotationalmovement so as to prevent misalignment within a bodily lumen.
 21. Theendovascular delivery system of claim 18, wherein the prosthesiscomprises non-textile polymeric material.
 22. The endovascular deliverysystem of claim 21, wherein the non-textile polymeric material of theprosthesis comprises extruded polytetrafluoroethylene.
 23. Theendovascular delivery system of claim 22, wherein said extrudedpolytetrafluoroethylene is non-porous polytetrafluoroethylene.
 24. Theendovascular delivery system of claim 18, wherein the prosthesis furthercomprises a metallic expandable member securably disposed at or near theopen end of the main tubular body of said bifurcated prosthesis.